Thanks for you work on this. Although there are standalone compilers for compiling AROS programs (running on AROS, Linux, and maybe Windows), you're less likely to encounter weird problems if you build the source tree under Linux (this creates the necessary compilers). This is especially true when developing system components, such as datatypes. We don't really have the manpower at the moment to support multiple development environments.

If you don't already run Linux and don't want to dedicate a machine to it, you can run Linux in a virtual machine on top of Windows. Ubuntu is probably the distribution that's been tested most for compiling AROS. Linux-hosted AROS is also the easiest environment to test AROS software in most cases.

miker wrote:Could you message me about the correct way to upload images? I already have some test bitmaps selected that are small enough to upload.

For BMP test images, the best location in SVN would be developer/debug/test/datatypes/bmp (relative to trunk's root, i.e. https://svn.aros.org/svn/aros/trunk/AROS). But please be sure that distribution is allowed and update the "LEGAL" file there.

You should commit to the trunk. ABIv0 and ABIv1 binaries are completely incompatible. If you want to test your datatype changes under ABIv0, download the ABIv0 sources from either the website or SVN and compile it as you would ABIv1.

miker wrote:I discovered that the Banding Effect that is seen in nearly every 8bit image, if it isn't black, happens when any 8bit image exceeds width=320, height=200. Anything larger than 320x200 will have the Banding Issue. So what causes it, and why are some images completely black? The blackness usually indicates no color palette associated with the image. Not sure at all why the weird banding effect is happening.

I have at least one counterexample: developer/debug/test/datatypes/bmp/neural.bmp from the SVN source tree is 463x339x8 and displays fine for me on pc-i386 (ABIv0) and darwin-i386 (ABIv1). It would be useful if you could provide links to your test images or upload them to the same SVN dir (if copyright allows).

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The code for the BMP datatype is overly and unnecessarily complicated. Even the smallest part is so obfuscated that it is difficult to understand what's going on. The Bitmap File Type is very simplistic, yet the datatype is overly complicated and very buggy!

I agree with you about the DataType, but the format isn't that simple, as it has a lot of variations.

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The BMP Picture DataType will need to be completely re-written!

Yes, that's what I concluded after making some limited improvements to it. It would be a pity to have to do so if Gunther's code could be used instead. So a "no" from him would be more useful than no answer

I think I put a set of test BMP images in the test directory (which might be "developer/debug/test" currently - I'm on holidays and on my phone, so I can't easily check). They may include <8-bit images.

A few years back, I made some improvements to the BMP data type, but realised there was a lot more to do. I found an alternative that has the source available but not under an open source licence. I emailed the author, Gunther Nikl about relicensing but got no reply. If you want to try contacting him again it might be worthwhile. Perhaps I didn't use the right address.

Please test with the V6.27 HDAudio driver I posted recently. If it doesn't work, try the version in Storage in Icaros to get a log to send me and I'll take a look when I return from holidays in about a week.